Conventional embroidery units generally used are attached detachably to a sewing machine bed and includes an embroidery frame, a Y-carriage mechanism to which an embroidery frame is detachably attached, a Y-transfer mechanism moving the Y-carriage mechanism in a longitudinal direction (Y-direction) of the sewing machine bed and an X-transfer mechanism moving the Y-carriage mechanism to the lateral direction (X-direction) of the sewing machine bed with the Y-transfer mechanism. By attaching the embroidery unit to the sewing machine bed, the embroidery frame is transferred to the X and Y-directions forming an embroidery pattern on the work piece cloth retained by the embroidery frame.
JP-A-2002-52280 discloses an embroidery unit provided with a case having a flat upper surface and a longitudinally elongated movable case placed on the upper portion thereof. An X-direction transfer mechanism (corresponding to the X-transfer mechanism of the present disclosure) is installed in the case. A Y-carriage mechanism is placed on the upper portion of the case. A Y-direction transfer mechanism (corresponding to the Y-transfer mechanism of the present disclosure) and a part of the Y-carriage mechanism is installed in the movable case.
Since the Y-carriage mechanism and the movable case protrude from the upper surface of the embroidery unit, when normal sewing operation is performed with the embroidery unit attached, the Y-carriage and the movable case become an impediment. Thus, in case of performing a normal sewing operation, the embroidery unit needs to be removed from the main body of the sewing machine, requiring space to place the embroidery unit removed from the main body of the sewing machine.